Lubricating and guarding means for sewing machines



Feb. 10, 1953 H. RITTER 2,627,830

LUBRICATING AND GUARDING MEANS FOR SEWING MACHINES 3 Sheets-Sheet 1 Filed March 4, 1947 IN VEN TOR.

N Herman Fitter win/5.5.: a

. p. 5: I M 404/ ATTORNEY H. RlTTER Feb. 10, 1953 LUBRICATING AND GUARDING MEANS FOR SEWING MACHINES 3 Sheets-Sheet 2 Filed March 4, 1947 IN VEN TOR.

Herman Hitter ATTORNEY H. RITTER Feb. 10, 1953 LUBRICATING AND GUKRDING MEANS FOR SEWING MACHINES Filed March 4, 1947 3 Sheets-Sheet s f ,N a

V IN VEN 10R. Harm an R1 fiber ATTORNEY wmvzss Patented Feb. 10, 1953 LUBR-ICATING AND GUARDING MEANS FOR SEWING MACHINES- Herman Bitter, Cranford, N. J., assignor to The Singer Manufacturing Company, Elizabeth. N. 1., a corporation of New Jersey Application March 4, 1947, Serial No. 732,173

4 Claims.

This invention relates to sewing machines and it has as a primary object to provide improved means for eifectively lubricating certain movin parts thereof and for preventing escape of the lubricant from the machine or to the outer surfaces thereof.

Another object of this invention is to provide, in a sewing machine in which the head is upwardly inclined rearwardly, as disclosed in United States Patent of A. B. Clayton, No. 2,394,511, February 5, 1946, improved means to prevent the escape of oil through the joint between the front face of the open bracket-arm head and the face-plate thereof, without the use of gaskets or similar sealing devices. This is effected by a drainage system which carries the oil away from said joint and thereby prevents it from seeping therethrough.

A further object of the invention is to provide an improved guard for the vibratory thread take-up arm of a sewing machine, which will prevent accidental contact of the operator with said arm and which will also function to return to the bracket-arm head any oil which is thrown off by the take-up arm, by its vibrating movements.

With the above and other objects in view, as will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying drawin s of a preferred embodiment of the invention, from which the several features of the invention and the advantages attained thereby will be readily understood by those skilled in the art.

In the drawings,

Fig. 1 is a longitudinal sectional view of a sewing machine embodying the present invention.

Fig. 2 is an enlarged left end view of the machine illustrated in Fig. 1, with the face-plate omitted and with certain parts shown in section.

Fig. 3 is an inside view of the face-plate which is omitted from Fig.2.

Fig. 4 is a sectional view of the bracket-arm head taken substantially on the broken line 44 in Fig. 2.

Fig. 5 is a rear view of a portion of the bracketarm head, illustrating, more particularly, the presser-bar lifting means.

Fig. 6 is a perspective view of an oil-guard which is mounted in the bracket-arm head, forwardly of the needle-bar, and which carries wicks for conducting oil to certain bearings hereinafter mentioned Fig. '7 is a perspective view of a second oil guard which is mounted in the bracket-arm head, rearwardly of the needle-bar, and which likewise carries a wick for conducting oil from a. sump in thebracket-arm head to a point where it is picked up by moving elements in said head.

Fig. 8 is a detail vertical section through the bracket-arm head, taken substantially on the line 88 of Fig. 4, showing the relationship of a guard member with a slack-thread regulator slot in the bracket-arm head.

Referring more specifically to the drawings, the invention is disclosed as embodied in a sewing machine having a frame including a horizontally disposed work-supporting bed I, from one end of which rises the standard 2 of a bracket-arm 3 terminating at its free end in a hollow bracket-arm head 4 overhanging the work-support. The head 4 is normally closed by a removable face-plate F hereinafter to be described.

Journaled lengthwise of the bracket-arm, in bearing bushings 5, B and I, is a main or drive shaft 8 which carries, at its rear end, a combined belt and hand-wheel 9 which may be driven from any suitable source of power.

Mounted in bearings I0 and H, in the head 4, for endwise reciprocation, is an inclined needle-bar I2 which carries, at its lower end. an eye-pointed thread-carrying needle l3. Upon the forward end of the shaft 8 there is secured a crank-disk [4 which carries a crank-pin 15 upon which is journaled the apertured hub l6 of an angular thread take-up lever H. To the outer end of the crank-pin I5 is secured one end of a crank-arm Hi, the other end of which carries a crank-pin 19 upon which is journaled the apertured hub 20 of a link 2| the lower end of which is journaled on a stud 22 carried by a split collar 23 secured upon the needle-bar 12. An anchor link 24 is journaled on a stud 25 in the bracket-arm head and is pivotally connected at 26 with the take-up lever H. The outer free end portion of the take-up lever passes through a slot l in the head 4 and is provided with a thread-eye '21 through which the needle thread passes in its travel from a conventional threadtension 28 to the eye of the needle [3. I

From the foregoing it will be understood that rotation of the main shaft 8 effects endwise reciprocation of the needle-bar, and the needle carried thereby, and vibratory motions of the take-uplever 11, all as is common in lock-stitch sewing machines.

Cooperating with the needle [3, in the formation of stitches, is a rotary loop-taker L, of conventional form, carried by the forward end of a horizontally disposed loop-taker driving shaft 29 journaled in bearings 30 and 3t beneath the bed I This shaft 29 is driven at a ratio of 2-to-1 from the main shaft 8 through the medium of a pair of bevel gears 32, 33, an inclined shaft 34 journaled in the standard 2 and a second pair of bevel gears 35, 38 connecting the shaft 3 with the shaft 29.

The machine is also provided with work-feeding mechanism, designated generally as i, which also is actuated from the main shaft 3.

Inasmuch as the specific construction of the stitch forming and work-feeding mechanisms are conventional, and form no part of this invention, detailed illustration and description thereof is deemed unnecessary.

Mounted in the bracket-arm head 4, rearwardly of and parallel to the needle-bar is a spring-depressed presser-bar 31, carrying, at its lower end, a presser-foot 38 which cooperates with the feeding mechanism to effect feeding of the work. Secured to the presser-bar 37, adjacent its upper end, is a collar 39 carrying a slack-thread regulator arm 40 having a portion which overlies the needle-thread in its passage from the tension 23 to the take-up eye 27. Forwardly of the needle-bar, the arm 40 is. off-set laterally toward the standard 2, as shown most clearly in Fig. 4, and projects through a slot 4! in the front wall t of the bracket-arm head. This slot is so located as to be shielded by one of two oil guards hereinafter to be described, thereby preventing oil being thrown from. the bracket-arm head through said slot. The collar 38 is provided with a rearwardly extending arm; 52 having a head 43 which slides between the walls of a slot id formed in the rear wall 4 of the bracket-arm head to prevent turning. of the presser-bar.

Pivotally mounted at the rear side of the bracket-arm is a Dresser-bar lifting lever 55, the forward end of which, asshown in Figs. 4 and 5, carries a stud t which projects through a slot 3'! in the rear wall 4 of the bracket-arm head. Surrounding the inner end of the stud adjacent the head lt thereof, is one looped end it of an L-shaped wire link 43, the other looped end $8 of which surrounds the presser-bar beneath the collar 39. The lever 45 may be turned about its pivot, to eifect lifting of the presser-bar, and the presser-foot carried thereby, by a rod 48 (Fig. 2) adapted to be actuated by any suitable. means such, for example, as by the knee-control means disclosed in U. S. patent of R. Kaier, No. 2,250,992, July 29, 1941.

The presser-bar may also be lifted manually by a hand-lever 56 pivotally mounted on a screw 5| threaded into. the rear wall 4 of the bracket-arm head. The lever 56 is provided with a. head 52 having two oppositely extending cam surfaces 52* and 52 each adapted; to. engage a horizontally flat surface 45 on the under side of the. lever l5. Thus the presser-bar, and the presser-foot carried thereby, may be lifted by turning the lever 6i) either clockwise or counterclockwise from the position illustrated in Fig. 5.

The needle-bar l2 and the presser-bar .3? are preferably upwardly inclined rearwardly as, and for the purpose, set forth in the above mentioned Clayton Patent No. 2,394,511.

In use, the machine is mounted upon a cast metal base B having, at one end an oil reservoir R. Secured to the under side of the work-supporting bed I is a pump P adapted to draw oil from the reservoir and to discharge it through a pipe 53 extending upwardly within the standard 2. The pump P is driven from the lower end of the inclined shaft 34 in the machine standard.

Oil discharged by the pump through the pipe 53 enters a cavity 6 in the bearing bushing 6, from which it is delivered through a radial duct 8 into a longitudinal bore 8* in the shaft 8. Within the bearing bushing 5 the shaft 8 is formed with a radial duct 54 through which oil flows from the bore 8 to lubricate the shaft bearing surface within the bearing bushing 5. A spiral groove 55, formed in the outer surface of the shaft 8, forces oil along the bushing and back into the bracket-arm. If any oil should leak from the front of the bushing, it is caught and returned into the bracket-arm by a downwardly inclined conduit 55 in the bushing 25.

To lubricate the take-up and needle-bar actuating mechanisms which are located, in the hollow bracket-arm head, a pan-like member 56 is secured in the upper end of the head, by a screw 58, and has a portion 59, extending through an aperture in a wall 3 of the bracket-arm which carries the bearing bushing 5, and which communicates with a well 59 in said wall 3*. The well 59 receives oil through the radial duct 54 in the shaft and a cavity (it in the bearing bushing 5. A wick 82, carried by the member 51, has one end located in the well 58 and its other end connected with wicks threaded through and extending below pipes 63, (it, G5 which depend from the member El. The depending ends of the wicks in the pipes 63, t l and 55 are held in such position that oil thereon is wiped off by certain moving parts of the take-up and needle-bar driving mechanisms within the hollow head. The above described portion of the lubricating system is generally similar to the lubricating system disclosed in United States patent of R. Kaier No. 2,206,285, July 2, 1940 to which reference may be had for a more complete disclosure.

Mounted in the bracket-arm head i, as by being secured to the needle-bar bearing H, screw 65, is a vertically disposed oil-guard, designated generally as G, which serves to prevent oil, thrown ed by the moving parts of the take-up and needlebar. actuating mechanism, from escaping from the head through the slot 3! through which the slack-thread regulator arm (iii extends. This guardmember also serves to support certain oil conducting wicks later to be described. The guard, which is shown detached in Fig. 6, comprises a substantially U -shaped portion 8? which partially surrounds the bearing ii, a forwardly extending flat Wall 63, and a laterally extending wall 69 having a depending portion 5E termihating in a tapered and rearwardly curved end portion it! which forms a chute for deliveringoil to asump H located in the lower end of the hoilow head The wall 66 is located between the moving parts of the take-up and-needle-bar actuating mechanisms and the slot 4! and intercepts and conducts, to the sump ll, oil thrown off by such parts. For the purpose of lubricating the reciprocatory needle-bar, a wick E2 is threaded through the walls 58 and 53 of the oil-guard. and the oil, as it travels down along the walls and 65?, saturates the wick 1.2 so that its freeend 12, which lies against the needle-bar, will adequately lubricate the needle-bar. Secured in the wall til and the end portion 19 of the guard member G is an oil-conducting wick 73 the lower free end of which is located in the sump 7! and draws oil therefrom. An intermediate portion 13, of

the wick I3, is maintained within the path of movement of the apertured hub at the lower end of the needle-bar reciprocating link 2| and delivers oil thereto for lubrication of the stud 22.

Located within the head 5, beneath the crankdisk I4, is a second oil sump 14 (Fig. l) which also receives oil thrown off by the take-up and needle-bar actuating mechanisms. Secured within the head 4, rearwardly of the presser-bar, as by screws 75, is a second vertically disposed oil-guard designated generally as H. This guard, which is shown detached in Fig. 7, has a portion 16 which lies between the take-up and needle-bar actuating mechanisms and the slot Al, in the rear wall of the bracket-arm head, through which passes the presser-bar lifting stud it. The guard member also has a downwardly and inwardly extending portion H the lower end of which overlies the oil sump it. Thus oil thrown off by the take-up and needle-bar actuating mechanisms is intercepted by the guard H and prevented from escaping through the slot 4?. This oil flows downwardly along the inner face of the guard and drips off the portion '51 into the sump M. The guard H also has an upper inwardly deflected portion 78 having apertures iii and 85 through which project, respectively, loops 8% and Bi forming parts of a wick 8! which extends -down wardly and has its looped lower end 82 located within the sump M, to draw oil therefrom.

The wick BI is surrounded by a coil spring 82 which gives to the wick a certain amount of rigidity and facilitates insertion of the looped end 8 i into the sump M. The spring 82 also prevents accidental displacement of the wick from the sump durin shipment of the machine and when the machine is inverted for inspection or repair. The loops 81 and Bi are maintained, respectively, within the paths of rotation of the apertured hub it of the take-up lever I1 and the apertured hub 20 of the needle-bar reciprocating link 2|. Thus those hubs pick up oil from loops {H and Bi thereby amplifying the lubrication effected by oil from the wicks in the pipes 83, Ed and 65, hereinbefore mentioned.

It will be noted that the open upper end of the sump It is materially above the open upper end of the sump l I. This higher elevation of the sump M enables the oil therein to be conveyed to the apertured hub 16 of the take-up lever l? and to the apertured hub 26 of the needle-bar driving link by a materially shorter wick 85 than would be possible if the sump were located in the lower end of the bracket-arm head, as is the sump H Inasmuch as the amount of oil capable of being conveyed by capillary action through any given wick is inversely proportional to the length of the wick, this shortening of the wick 8!, by elevation of the oil level in the sump is, materially increases the amount of secondary, or used, oil returned to the needle-bar driving and. take-up mechanism. This secondary lubrication of the take-up and needle-bar driving mechanisms is supplemental to the primary lubrication thereof which is effected from the pan-like member 57 by the wicks which extend through the pipes 63, 64 and {55, as hereinbefore described. The combined primary and secondary lubricating means effect generous lubrication of the take-up and needle-bar mechanisms. So much so, in fact, that without the guard devices herein described, oil thrown off by these mechanisms, and sprayed around in the bracket-arm head, would escape 6 from the head, much to the inconvenience and annoyance of the operator.

Due to the whipping action of the take-up lever l1, there is a tendency for oil to creep along the lever and to be thrown off the free end there of, which normally is exposed at the front side of the bracket-arm head. To protect the operator against accidental contact with the takeup lever and also to catch any oil which may be thrown off thereby, this invention has provided an improved guard member within which the free end of the take-up lever operates without interfering with the normal travel of the needle thread. This guard comprises a cast member 83 which is secured by screws 84 to the wall 4 of the bracket-arm head. The member 83 is provided in its rear wall with a slot 83 which is aligned with the slot 4 for passage of the take-up lever. The side Walls 85 and 86 of the member 83 are formed with curved apertures 81 and 88 which are so shaped as to permit the needle thread T to pass therethrough, without coming into contact with the side walls during the normal'movements of the take-uplever. Thus the guard does not affect the normal operation of the take-up or the normal run of the thread from the tension 23, through the take-up eye 21, to the needle. As seen most clearly in Fig. 4, the outer portion 83 of the member 83 is substantially U-shaped in transverse cross section. This forms a downwardly extending curved chute 83 which catches any oil thrown off by the take-up lever and conducts it to the bottom of the guard, from which it flows through aligned ducts 89 and 56 formed, respectively, in the guard member and the wall 6*, back into the bracket-arm head land finally intothesumpll.

The face-plate F, hereinbefore mentioned, is preferably made of cast metal and'is secured to the front of the bracket-arm head by screws 9| passed through openings 92 in the face-plate and threaded into the head. As hereinbefore stated. the bracket-arm head is inclined rearwardly; therefore the face-platesecured thereto is likewise inclined. It has been found that with the parts so inclined there is a tendency for the oil which comes into contact with the inner wall of the cover-plate to creep to the back and seep out through the joint between the bracket-arm head and the face-plate. This seepage may, of course, be prevented by the employment of a suitable gasket between the head and the cover-plate. However, in view of the fact that the cover-plate frequently has to be-removed, the use of a gasket in this joint is'undesirable as the removal and replacement of the cover-plate soon damages the gasket and permits leakage of oil.

This invention has provided an improved construction in which the face-plate may have a metal-to-metal contact with the bracket-arm head without permitting seepage of oil therebetween. This has been effected by providing milled contacting surfaces g on'the head and complemental milled surfaces 9' on the face-plate F and providing means within the face-plate to drain the oil away from the joint therebetween and for delivering it into the sump H. To that end, the face-plate is formed, on its imier surface, with a series of projecting ribs 93 which are inclined downwardly and forwardly as shown most clearly in Fig. 3 and aiford, between them, downwardly and forwardly inclined channels or valleys c which drain the oil away from the rear joint between the head and the face-plate. Beneath the ends of ribs 93, the face-plate is formed with an inwardly extending horizontally disposed shelf or ledge 94 over the edge of which the oil, from the valleys v, flows and ,gravitates into a cavity in the .lower end of the bracket-arm head and finally into the sump H. A sheet metal shield 95 is secured, by screws .96, .to the face of the bracketarm head beneath the shelf at and together with the walls of the head forms an oil-collecting cavity and serves to prevent escape of oil from the lower end of said head. Inasmuch as this shield need not be removed from the head, when access to the head is desired, a conventional gasket is may be used between the shield and the head to effect an oil-tight joint.

Having thus set forth the nature of the invention, what I claim herein is:

1. In a sewing machine having a frame including an upwardly and rearwardly inclined hollow bracket-arm head and a similarly inclined faceplate removably secured thereto in metal-tometal contact, said face-plate having a portion exposed to oil thrown off by mechanism in said head; the improvement which comprises the provision, on the inner face of said face-plate, of forwardly and downwardly inclined channels for directing the oil received thereon, downwardly and forwardly and away from the rear joint between the head and the face-plate, and a substantially horizontally disposed shelf beneath the lower ends of said channels for conducting said oil laterally of said face-plate and depositing it into the lower end of the bracket-arm head.

2. In a sewing machine having a frame including an upwardly and rearwardly inclined hollow ,7 open-faced bracket-arm head and a similarly inclined face-plate removably secured to the forward face of said head in metal-to-metal contact, said face-plate having an upper inner portion exposed to oil thrown ofi by mechanism in said head and a lower inner portion spaced from said forward face of the bracket-arm head; the improvement which comprises the provision of a vertically disposed sheet metal shield secured to the lower end of said head intermediate the head and said lower portion of said face-plate and coopcrating with the walls of said head to form an oil-collecting cavity; ribs formed on the inner face of said face-plate and afifording between \hem valleys for directing the oil, received thereon, downwardly and forwardly and away from the rear joint between the head and the face plate; and a substantially horizontal ledge formed in said face-plate beneath said valleys and inwardly overhanging the upper edge of said shield, said ledge serving to deliver to said cavity the oil received on the inner face of said face-plate and transmitted to the ledge by said valleys.

2.. In a sewing machine having a frame including a hollow bracket-arm head having an oil sump in its lower end, and a face-plate secured to and closing said head, said face-platehaving portions exposed to oil thrown off by mechanism in said head; the improvement which comprises the provision of inclined channels on substantially the entire inner surface of said face-plate for diresting all of the oil, received thereon downwardly and away from a joint between the head and the face-plate, and a horizontally disposed ledge on said face-plate below said. channels and overhanging said oil sump for receiving the oil from the channels and conducting it laterally and delivering it into the sump.

4. In a sewing machine, in combination, a frame including a hollow bracket-arm head affording an oil reservoir within the bottom of its hollow portion, said head having a slot formed in one side wall thereof and communicating with the hollow formed in said head at a location laterally spaced from said reservoir; a needle-bar and actuating mechanism therefor in said head; a presser-bar mounted in said head; a presserbar lifting mechanism including a member extending through the slot in said wall; a vertically disposed oil-guard mounted in said head at one side of said reservoir and between the actuating means for said needle-bar and said slot, to pre I vent oil, thrown off by said actuating means, from passing through said slot; a finger extending laterally from said oil guard to have its free end portion disposed over said reservoir to return thereto oil deposited upon said guard; and an oileonducting wick carried by said guard and having one portion located in said reservoir and another portion located in the path of movement of a part of said needle-bar actuating mechanism to deliver to said mechanism oil picked up from said reservoir.

HERIfiAN BITTER.

REFEQENCES CETED The following references are of record in the file of this patent:

UNITED STATES Z ATENTS Number Name Date 644,036 Stephenson Feb. 20, 1900 923,824 Eidam June 8, 1909 1,334,088 Goldstone Mar. 16, 1920 1,507,597 Greenwood Sept. 9, 1924 1,955,580 Fleckenstein Apr. 17, 1934 2,047,730 Fleckenstein July 14, 1936 2,156,547 Smith May 2, 1939 2,254,050 Stadub Aug. 26, 1941 2,268,319 Barron Dec. 30, 1941 

